Research on Fault Characteristics of DFIG Wind Farm with Flexible DC Integration

At present, China’s offshore wind power generation technology has a lot of room for development. As the offshore distance of offshore wind farms grows, the traditional AC integration approach has gradually been replaced by the flexible DC transmission integration approach. The difference from the traditional AC integration approach is that there are a multitude of power electronic devices in the VSC-HVDC system, which makes the fault characteristics of the system greatly changed. This paper mainly studies the fault properties of doubly-fed induction generator (DFIG) with flexible DC integration. Firstly, the topology and control strategy of DFIG Wind Farm with flexible DC integration are analyzed, and a mathematical model of the system control part is established. Secondly, the DFIG short-circuit current is calculated, and the factors affecting the size of the short-circuit current are found through analysis. Finally, the fault characteristics are analyzed by building a DFIG Wind Farm model with flexible DC integration on the PSCAD/EMTDC simulation platform.